Method of making innoxious the resin in cellulose which is intended for the manufacture of paper.



' UNITED STATES PATENT OFFICE.

sIevARi) FREDRIK LAGEBMARCK METHOD OF MAKING INNOXIOUS THE RESIN IN CELLU LOSE WHICH IS INTENDED FOR AND WILLIAM SVERDR-UP, or non," nmsvoim.

NORWAY.

THE MANUFACTURE OF PAPER.

No Drawing.

To all whom it may concern:

. Be it known that we, SIGVARD Fnnnnn; LAGERMARCK, director, and \VILLIAM Sven- DRUP, engineer, subjects of Norway, residing at Bon, pr. Eidsvold, Norway, have invented new and useful Improvements in Methods which is Intended for the Manufacture of of Making Innoxious the Resin in Cellulose Paper, of which the following is a specification.

In the manufacture of paper from a mixture of cellulose and wood-pulp or from cellulose alone inconveniences and working disturbances have occurred to a greater or less extent because resin is deposited on suction-boxes, wires, cylinders or other parts of the paper making machines. When the machine does not operate at a high speed the difliculties are small in connection with,

usual carefully boiled cellulose, but in case of modern high speed'paper making machines the resin is very inconvenient. In the order to make the resin innoxious, but on the one, hand when this substance is used in small quantities it yields only a little or no help, whereas on the other hand the quality of the paper to be manufactured does not permit the use of larger quantities of kaolin.

By washing cellulose, such as is obtained from the boilers, with a thin talcum-milk,

we have found that no talcum was deposited in .thegla'ss. The talcum consequently had been taken up by the cellulose fibers, and it was supposed that it had adhered to-the resin which is outside the cellulose fibers. We then made an attempt on a large scale by adding 10% of talcum to the cellulose coming from the hutches into which the cellulose is blown out from the boilers and from which it passes to the separators. The result was veryfavorable.

The method forming the objectof the present invention therefore consists in adding Specification of Letters Patent;

Patented Nov. 23, 1915.

Application filed April 6, 1915. Serial No. 19,553'.

talcum (kaolin, sulfate of barytes or the like) to the cellulose just as it passes to the separators serving to separate the single fibers from each other and in which the cellulose and talcum are rubbed intimately together. The effect of the mass being treated by talcum in the separators probably depends upon the'noxious adhesive resin being enveloped by talcum so as to neutralize its adhesive properties. The cellulose is thereafter treated in usual manner, it being passed to the sand-precipitators, through strainers and from thence to the paper makmg machines. Some talcum is left in the sand-precipitators, and hereby probably some part of the resin is removed because it is taken along to the bottom, but the substantial effect, upon which the favorable result depends, follows from the said treatment of the mass in'the separators.

In the manufacture of paper which is smooth on one side such as is efiected in Yanky-machines having a large cylinder, and sometimes small cylinders next thereto, the paper becomes smooth on account of the essential, and at all events the final, drying taking place on the large cylinder. It

therefore is of essential importance that this large cylinder is always absolutely smooth or shining. This is very difficult to obtain, because the cylinder cannot be kept clean from resin and substances adhering thereto. But if talcum is added as described above the cylinders .are maintained quite clean. The paper will be much more nicely and sharply calender-ed, and just on account of the talcum being added in the separators before'water is added to the mass the quantity of talcum (kaolin, sulfate of barytes etc.) necessary is much less than that hitherto used, when substances of similar sort have been added in the cellulose-boilers themselves during the boiling of the mass under pressure, The last mentioned method is also" expensive and time-wasting, because the liquid, "after the mass has been boiled,

must first be blown oif,the cover then again be placed on the boilerwh-ich usually must be rotating, whereupon talcum-milk is pumped in and the mass is subjected to steam pressure.

/ In our method a quantity of 8% of talcum may suitably be added to the cellulose.

The method is very simple, because the of talcum other mineral substances such as kaolin, asbestos powder or other filling substances may be used.

Having now described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A method ofmaking innoxious the resin contained in cellulose which is intended for the manufacture of paper or for similar purposes, characterized by a filling substance .(such as talcum kaolin, sulfate of barytes or the like) being added to the cellulose only when the latter-after having left the boiler and after having been rid of the boiling liquid and washed in the hutches, but before the addition of diluting water has taken place is to be subjected to the treatment in the separators and succeeding devices, whereby the particles of resin, in a state of fine distribution throughout the mass, are enveloped by the filling-substance so as to lose their adhesive properties.

resin contained in cellulose which is intended for the manufacture of paper or for similar purposes, characterized by a filling substance (such as talcum, kaolin, sulfate of barytes or the like) being added to the cellulose only when the latterafter having left the boiler and after having been rid of the boiling liquid and Washed in the hutches, but before the addition of diluting water has taken placeis to be subjected to the treatment in the separators and succeeding devices, whereby the particles of resin, in a state of fine distribution throughout the mass, are enveloped by the fillingsubstance so as to lose their adhesive properties, the amount of talcum in relation to cellulose being about 8%.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

SIGVARD FREDRIK LAGERMARCK. WILLIAM SVERDRUP.

\Vitnesses:

AXEL ZAHN, MOGENS Biiccn. 

